CE approval

PLT interference

I am a radio amateur and thus far I am not plagued by interference from these infernal interference devices.

There are a lot of misconceptions bandied about about the amateur radio fraternity and the interference that WE cause.

We are a licenced service and have to ensure that our equipment meets emc and other regulations and that we do not cause interference to other users of the spectrum. If we do, we can be REQUIRED to close down our station and could lose our licence. If computer buffs had to undergo the same examinations and training re: the nature and propogation of radio waves, they, or at least the responsible ones, would not condone the use of plt devices.

Plt devices have been subjected to independent tests which have shown that, despite carrying a CE stamp they DO cause interference in the order of 1000 times the permitted levels. The Comtrend ones issued with BT Vision are the worst but none are 'clean'. To say they are notched around the amateur bands is a bit like saying that providing that I notch my transmitter so that I only interfere with BBC2 and Channel 5, that would be OK as they are minority interest channels. The very existence of any notching is an ADMISSION of GUILT and that they DO cause interference, that alone should be enough to get these devices withdrawn from the marketplace (if only until they have been tested and made to conform to the legislation, which I fear is actually impossible). The only effective 'notch' for these devices is one covering the WHOLE of the HF spectrum from 0-30MHz.

@ Gene Cash

To say there have been no complaints to the gov't is clearly wrong.

The UKQRM group, and many individuals, have made numerous representations to mp's and various dept's only to get fobbed of with the Ofcom 'message' that there have only been a few claims of interference from amateurs and swl's therefore there is not a real problem.

There have also been 2 petitions to Downing Street, both of which resulted in ministerial waffling, whitewashing responses.

Regardless of who 'hears' interference and who complains about the interference - the fact remains that interference to shortwave bands IS being caused by plt devices and it IS Ofcom's statutory duty to deal with ALL cases of interference.

The issue is that they (Ofcom) are choosing to ignore the issue of plt interference. This inevitably leads to the suspicion that Ofcom is being driven by a hidden agenda. Probably this agenda is to support BIG BUSINESS at the expense of the LITTLE MAN.

@ anonymous coward, Sell what spectrum?

"Ofcom should punish these luddites for thier law suit by selling off thier spectrum to someone who might actually use it or better still, revoke their license and bag the frequencies for some future technology."

The spectrum is used by international agreement by users around the world, including broadcasters, maritime, aviation and military users, as well as amateurs and cb radio, so is NOT available for ANYONE to sell to anyone.

Apart from that fact, WHO would want to buy a radio spectrum which has been made totally unusable by the proliferation of illegal plt/bpl devices, which splatter their evil digital hash everywhere.

@Peter Gathercole

I appreciate your statement about wanting to be a good neighbour, but I think that 'good neighbour' and 'plt devices' are impossible bedfellows.

Take a look at the site www.ukqrm.co.uk and listen to some of the audio files posted on there. They will give you some idea of the crap that plt generates on the shortwave radio spectrum, if you have a radio in your house that is capable of receiving broadcasts on the SW band, just have a listen for yourself to the noise pollution emanating from your devices.

Yes, plt's are very convenient to use but are a rubbish technology which should never have been allowed onto the UK market because they use a part of the radio spectrum which is simply NOT AVAILABLE for use.

People should forget all about WHO is being affected and whether that is ok, because it is quite clear that Ofcom SHOULD be removing ALL sources of radio pollution, as is their remit.

There are perfectly ok alternatives to the PLT's that are causing interference, and that is ANY device which does not use the SW spectrum between 2-30mHZ, which I understand ARE available but are undoubtably more expensive, hence the proliferation of these CHEAPER devices being supplied by BT as part of their BT Vision package and available CHEAPLY in stores like Maplins.

These plt's are NOT enabling devices, they are just cheap alternatives using a set of frequencies which are already in use, and Ofcom should require their removal unconditionally.

Ofcom not fit for purpose!

PLT's are (poorly) notched so as to NOT allow interference on some of the amateur bands but is only partially effective - this however does not stop the interference in other parts of the HF spectrum, thus interfering with Short Wave Listeners winkling out those weak signals, and those who would wish to listen to foreign broadcast stations still operating legally in these bands.

The very fact that PLT's have notches is an admission by the manufacturers that they DO CAUSE illegal interference. Ofcom are therefore neglecting their duty to remove an interfering device.

If a technology was introduced that kept breaking through on Coronation Street or Jeremy Kyle the masses would soon be up in arms.

Why should the followers of the perfectly legal hobbies of amateur radio, shortwave listening and citizens band radio not be similarly outraged. They should therefore get suitably protected by the Government body, paid by the taxes of those very same hobbyists to regulate the interference to the radio spectrum?

It would appear that Ofcom are following an agenda OTHER than that of dealing with interference from whatever cause, which is there reason for being, therefore I say that they are 'Not Fit For Purpose' unless they are prepared to 'Do Their Duty' and remove PLT devices forthwith.